Apparatus for grinding bricks or the like



Dec. 20, 1966 M. A. LEFEVRE APPARATUS FOR GRINDING BRICKS OR THE LIKE 6Sheets-Sheet 1 Filed Feb. 20, 1964 INVENTOR.

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APPARATUS FOR GRINDING BRICKS OR THE LIKE Filed Feb. 20, 1964 6Sheets-Sheet 73 FIG. 5 s2 52 INVENIOR." MARTIAL A. LEEEVRE BY A f ATT'YDec. 20, 1966 M. A. LEFEVRE APPARATUS FOR GRINDING BRICKS OR THE LIKE 6Sheets-Sheet 3 Filed Feb.

INVENTOR.

MARTIAL A. LEFEVRE ATT'Y 6 Sheets-Sheet 4 ATT'Y Dec. 20, 1966 M. A.LEFEVRE APPARATUS FOR GRINDING BRICKS OR THE LIKE Filed Feb. 20, 1964 kv WEE. 4 won A L 4 m T m v 05 B mo 2 51 M o? 3? ok A 9N N ig oov I wow9;

m m m\||illll|. Q @OE Dec. 20, 1966 M. A. LEFEVRE APPARATUS FOR GRINDINGBRICKS OR THE LIKE Filed Feb. 20, 1964 6 Sheets-Sheet 5 INVENTOR.MARTIAL A. LEFEV RE ATT'Y Dec. 20, 1966 LEFEVRE 3,292,310

APPARATUS FOR GRINDING BRICKS OR THE LIKE Filed Feb. 20, 1964 6Sheets-Sheet 6 FIG. 17

INVENTOR. MARTIAL A. LEFEVRE BY Q Al I

ATT'Y United States Patent 3,292,310 APPARATUS FOR GRINDENG BRICKS ORTHE LIKE Martial A. Lefevre, Oise, France, assignor, by mesneassignments, to International Diamond Products Limited, Shannon,Ireland, a corporation of Ireland Filed Feb. 20, 1964, Ser. No. 346,33923 Claims. (Cl. 51-118) The present invention relates generally to anapparatus for grinding bricks or similar -blocklike articles and hasparticular reference to an apparatus by means of which the surfaceirregularities that are ordinarily present in connection with buildingbricks as they issue from the kiln may be rectified and the variousfaces of the bricks ground with a precision that has heretofore beenunattainable economically by conventional brick surfacing apparatus orequipment to the end that each finished brick presents flat andaccurately rectangular side and end faces which possess a remarkabledegree of smoothness, with the twelve edges of the brick being linearlystraight and devoid of burrs or interruptions, with opposite faces ofthe brick being truly parallel and with all of the rectified or groundbricks being of uniform size.

Bricks which are thus rectified or conditioned are capable of use in thegang forming of wall sections which are themselves of precisiondimensions. Due to the high degree of flatness of all six faces of eachbrick in a gang formed wall section, close proximity of adjacent opposed'brick faces may be attained with the bricks being separated from oneanother by a thin layer of a strong bonding agent, for example, an epoxyresin, resulting in an immeasurably stronger bond than when the bricksare bonded by a relatively thick layer of conventional mortar. By havingthe inside faces of the bricks of the wall sections fiat and coplanar,the usual lath and plaster installation may be omitted and the insidewall surfaces of a building structure thus erected from gang formed wallsections may be brush or spray painted, or otherwise decorated orsurfaced directly. By having the outside faces of the bricks of the wallsections flat and coplanar, similar treatment may be resorted to and,additionally, a building constructed of gang formed wall sectionsaccording to the present invention will present a finished appearancethat is commensurate with standards of modern architecture.

According to the present invention, brick surfacing operations arecarried out by means of a novel grinding apparatus which may becomprised of a single surfacing or grinding apparatus which employsrotary grinding wheels and through which the bricks of a given run aresuccessively passed three times, the first pass serving to condition onepair of opposite brick faces, the second pass serving to conditionanother pair of opposite brick faces, and the third pass serving tocondition the third pair of opposite brick faces and comple the bricksurfacing operations. When a single surfacing or grinding apparatus isemployed, it will be necessary, of course, to effect certain machineadjustments, such adjustments being mainly spacing adjustments of therotary grinding wheels and spacing adjustments of the brick clamping orholding devices by means of which the bricks are successively carried toand past the grinding wheels, the purpose of the last-mentionedadjustment being to accommodate the different dimensions between theopposite leading and trailing faces of the bricks during the threesuccessive passes through the apparatus.

Alternatively, the apparatus may be comprised of three basicallyidentical brick surfacing or grinding apparatuses which are arrangedside-by-side or in series and through which a given run of 'bricks issuccessively passed. In

"ice

this connection, it is contemplated that the first apparatus will beadjusted to handle bricks which are so oriented that, when passingthrough the grinding station, one pair of opposite faces of each brickwill be operated upon by the rotary grinding wheels. It is alsocontemplated that transfer means will be provided for conducting thebricks from the first apparatus to the second apparatus, the latterbeing so conditioned or adjusted as to receive and handle the bricks forpresentation of a second pair of opposite faces of each 'brick to thegrinding wheels of the second apparatus. Similarly, it is contemplatedthat transfer means will be provided for conducting the bricks from thesecond apparatus to the third apparatus, such third apparatus being soconditioned or adjusted as to receive and handle the bricks forpresentation of the third and last pair of opposite faces to thegrinding wheels at the grinding station of the third apparatus. Byutilizing three surfacing or grinding apparatuses, the time and laborincident to effecting change-over operations on a single surfacing orgrinding apparatus are eliminated.

Whether the apparatus as a whole involve the use of a single apparatuswhich must be adjusted for each run of bricks, or plural apparatusespermanently conditioned for successive runs, the essential features ofthe invention are at all times preserved, one such feature being thatafter the first pass of a given run of bricks, the two opposite faceswhich are treated then become reference faces for accurate clamping ofthe bricks during the next pass, whether in the same or in a differentsurfacing or grinding apparatus. Similarly, after the second pass of agiven run of bricks, the two opposite faces which are treated duringsuch pass become reference faces for accurate clamping of the bricksduring the third pass. Stated otherwise, after the first operation upona brick which may be irregular as to non-parallelism of opposite facesand also as to non-normality of adjacent side faces, two accuratelyplanar and parallel surfaces are established as a basis for grinding ofthe remaining brick faces to accurate conditions of parallelism andnormality.

The provision of a brick grinding apparatus of the character brieflyoutlined above being among the principal and general objects of theinvention, this object is attained by the provisions of one or moreapparatuses, each of which embodies a power-driven feed conveyor whichreceives the bricks at a receiving station and delivers them to agrinding stand where the bricks are processed. The grinding standincludes a rotary drum which receives the bricks from the feed conveyorat a transfer station and conducts the bricks in a securely held mannerto a grinding head at a grind ng station Where the bricks pass betweenthe opposed parallel planar sides of at least one pair of rotatinggrinding wheels which serve to condition the bricks by smoothing andrendering parallel two opposite faces of the bricks. From the grindingstation, the bricks are conducted by the drum to a delivery stationwhere they are discharged from the apparatus.

The feed conveyor includes an endless series of articulated travelingbrick-supporting trays, each of which is adapted to receive therein oneof the bricks to be ground. Releasable brick-supporting means isassociated with each tray for holding the associated brick in anapproximately oriented position. The feed conveyor is of the endlesslink type and the rotary drum to which it delivers the bricks includes aseries of brick-receiving cradles. The cradles of the drum are providedwith brick-clamping means which serve fixedly to secure the brickswithin the pockets of the cradles during passage of the bricks betweenthe rotating grinding wheels at the grinding station.

The movements of the feed conveyor and the cradle- J equipped drum arecorrelated so that successive trays arriving at the transfer station maydeliver their bricks to successive cradles on the drum arriving insynchronism at such station. The operation of the brick-supporting meanson the trays and the clamping mechanisms on the cradles is alsocorrelated so that substantially at the same time that thebrick-supporting means of a given tray at the transfer station releasesa brick to open" the tray and discharge the brick, the clampingmechanism of the corresponding drum cradle in register with the trayseizes the brick, thus closing the cradle uponthe brick and capturingthe same. The thus captured brick, rigidly positioned in the particularcradle, is conducted by the cradle through the grinding station and,after two opposite faces thereof have been conditioned, the brick isconducted to the discharge station where the cradle is caused to openand release the brick to a power-driven discharge conveyor.

In order to align the bricks accurately with the space existing betweenthe two rotating grinding wheels at the grinding station, a fixedcentering station is provided between the transfer station and thegrinding station. The bricks which are transferred from the powerdrivenfeed conveyor to the rotary drum of the grinding stand are thus causedto pass through the centering station. At this station, two centeringshoes on opposite sides of the bricks and in associated relation with abrick centering device are caused to engage the adjacent brick faces andthus forcethe bricks to accurately centered positions in circumferentialregister with the space existing between the two grinding wheels at thegrinding station which lies ahead of the centering station. Engagementof the bricks by the centering shoes is only momentary and, thereafter,the clamping mechanisms that are associated with the drum cradlesrigidly maintain the bricks thus centered during their passage to andthrough the grinding station, as well as thereafter and until such timeas the bricks are discharged from the drum.

The operation of the brick-supporting trays that are associated with andform a part of the feed conveyor is purely mechanical, novel cam means,including fixed cam tracks on the conveyor frame and cooperating movablecam fingers on the endless conveyor proper, being provided for effectingopening and closing movements of the various trays. The brick-clampingmechanisms that are associated with the rotary drum are hydraulicallyoperated, a novel system of trip fingers and stops being provided on thedrum-supporting structure and the drum respectively for effecting propertiming of the drum cradle opening and closing movements.

The provision of a brick grinding apparatus of .the character brieflyoutlined above being the principal object of the invention, numerousother objects not at this time enumerated due to their manifold andvaried nature will become readily apparent as the following descriptionensues. These ancillary objects are, in the main, concerned with novelassemblies and sub-assemblies associated with the apparatus such as feedconveyor and drum mountings, brick-receiving and retaining cradle andtray assemblies, correlation and timing of the movements of the cradleand tray assemblies, the centering device and its correlation with thefeed conveyor and the drum, facilities for machine adjustment foraccommodating bricks having different spacings of opposite faces,hydraulic circuitry, and other novel features too numerous to enumerate.

With such objects in view, the invention consists of the novelconstruction, combination and arrangement of parts shown in theaccompanying six sheets of drawings forming a part of this specificationand in which:

FIG. 1 is a side elevational view of a brick grinding apparatusconstructed according to the principles of the present invention andinvolving a feed conveyor for conducting bricks to a grinding machineproper forming a part of the apparatus;

FIG. 2 is a vertical transverse sectional view taken FIG. 7 is avertical sectional view taken substantially along the line 7-7 of FIG.6;

FIG. 8 is a circuit diagram of the hydraulic control mechanism forcontrolling the opening and closing movements of certain brick-conveyingcradles that are employed in connection with the invention;

FIG. 9 is a circuit .diagram of the hydraulic control mechanism forcontrolling the opening and closing move ments of a pair ofbrick-centering shoes that are employed in connection with theinvention;

FIG. 10 is an enlarged transverse sectional view taken substantiallyalong the line 1010 of FIG. 1;

FIG. 10a is a sectional view taken substantially along the line 10a10aof FIG. 10;

FIG. 11 is a sectional view taken substantially along the line 1111 ofFIG. 10;

FIG. 12 is an enlarged plan view of the brick centering device;

FIG..13 is a perspective view, entirely schematic in its representation,showing a brick which is to :be operated upon by the apparatus of thepresent invention and illustrating the orientational relationship of itsside and end faces with relation to the grinding head during successivepasses of the brick through the apparatus;

FIG. 14 is a schematic diagram further illustratingthe orientationalrelationship between the brick and the.

grinding head during an initial pass of the brick through the apparatus;

FIG. 15 is a schematic diagram illustrating the orientationalrelationship of a brick with respect to the grin-ding head during thefirst pass of the brick through the appa ratus;

FIG. 16 is a schematic diagram, similar to FIG. 15, but

illustrating the orientational relationship during the second pass ofthe brick through the grindinghead of the apparatus; and

FIG. 17 is a schematic diagram, similar to FIGS. 14 and 15, butillustrating the orientational relationship of a brick with respect tothe grinding head during the third or final pass of the bricks throughthe apparatus. 7

BRIEF DESCRIPTION Referring now to the drawings in detail and inparticular to FIGS. 1 to 4, inclusive, wherein a preferred form ofbrick-grinding apparatus constructed according to the present inventionhas been illustrated, the apparatus involves in its general organizationa power-driven feed conveyor 10 which extends between a brick-receivingstation R and a brick-transfer station T. At the transfer station T, thebricks are transferred from the feed conveyor 10 to a grinding machineproper 12 including a brick-clamping conveyor in the form of a rotarypowerdriven drum 14 by means of which the, bricks are conducted througha centering station C to a grinding station G and from thence to adischarge station D where the bricks are discharged onto an endlesspower-driven conveyor 16 by means of which the bricks are conducted fromthe apparatus as a whole.

As will be described in greater detail presently, the power-driven feedconveyor 10 is provided with a series of articulated brick-supportingand transporting trays 18 which transport the bricks from the receivingstation R to the transfer station T. At the transfer station, the trays18 are automatically manipulated into an open position in order todischarge the bricks by gravity. The rotary power-driven drum 14 isprovided with a series of articulated brick-receiving and dampingcradles 20. The drum 14 and the feed conveyor are driven in timedrelationship so that the cradles arrive at the transfer station T incorrelation with the trays 18, successive trays 18 arriving at suchstation being met by a corresponding cradle 20. Upon successive arrivalat the transfer station T, the trays 18 become automatically open torelease the bricks carried thereby so that they may be discharged bygravity into the cradles 20 which arrive at the transfer station in anopen condition. As soon as a brick is thus received in a given cradle20, the cradle automatical ly becomes closed in order securely to seizethe brick and conduct the same to the centering station C. The empty andopen trays 18 return to the receiving station R and, immediately priorto arrival thereat, they again become closed for repetitious receptionof bricks at such station.

Meanwhile, the cradles 20 on the drum 14 proceed successively from thetransfer station T to the centering station, at which station a pair ofcoacting centering shoes 22 forming parts of a centering device 24closes upon the opposite sides of the successive bricks on theirassociated cradle 20 and circumferentially aligns the bricks with twospaced apart rotary grinding wheels 25 which are disposed at thegrinding station G and constitute the abrasive grinding elements of agrinding stand 26. The bricks then pass between the grinding wheels 25which operate upon one pair of opposite faces of each brick and,thereafter, from the grinding station G, the bricks are conducted to thedischarge station D where the cradles 20 automatically become open todischarge the bricks onto the conveyor 16.

The bricks which are thus discharged onto the conveyor 16 will each haveone pair of opposite faces rendered smooth and planar, and what isequally important, truly parallel to each other. These two conditionedfaces of each brick may then constitute accurate reference faces forfurther brick conditioning operations when the thus preliminarilytreated bricks are passed through the grinding apparatus duringsubsequent runs, as will be described in detail subsequently.

THE FEED CONVEYOR The feed conveyor 10 is of the endless link type andcomprises identical functional link components which are connectedtogether in end-to-end relationship for travel in a closed pathincluding a feed reach section 27 (see FIG. 4) and a return reachsection 28; At the ends of the conveyor 10 the link components passaround driving and driven sprocket wheels 29 and 30. The conveyor 10 isof the horizontal pass type in that its driving and driven sprocketwheels rotate in respective horizontal planes, both reach sections beingelevated above the floor 31 of the establishment wherein the grindingapparatus is located. The individual link components are designated bythe reference numeral 32, and these components are guided in theirendless path of travel by conveyor rails 33 in the usual manner ofconveyor link travel. In the medial region of the conveyor 10 and asshown in FIG. 1, the conveyor rails 33 are inclined in order that therear end of the conveyor is higher than is the front end thereof, therear end overlying the grinding machine proper 12 at the transferstation T.

While the details of the individual conveyor link oomponents 32 remainthe same in any case, the effective contour of the conveyor 10 may bevaried in order to accommodate different kinds or types ofinstallations. The function of the conveyor 10 is to transfer bricksfrom a stockpile or source of such bricks to the grinding machine proper12 and, thus, under certain circumstances, it may be necessary to employa conveyor of great effective length, especially if the grinding machineproper 12 is located an appreciable distance from the stockpile ofbricks. The conveyor may be linearly straight or it may have curves orbends, as, for example, when the stockpile is disposed in a differentroom or enclosure from the grinding machine proper, or when anintervening object or machine requires such curves of bends.Irrespective, however, of the particular contour of the conveyor 10, theessential features of the invention are not altered.

In the exemplary form of conveyor 10 illustrated herein, the drivingsprocket wheel 29 is rotatably supported in a superstructure 34 whichforms a part of the stationary conveyor framework, the superstructurebeing in turn supported by vertical posts 35 from a masonry base 36 onthe floor 31. The rotary drum 14 of the grinding machine proper 12 ismounted on a horizontal shaft 38 which is supported in bearings 40 onthe masonry base 36. The driving sprocket wheel 29 of the feed conveyoris mounted on the upper end of a vertical drive shaft 42. The lower endof such shaft is operatively connected in driven relationship through agear box 44 and an articulated or universal coupling 45 to thehorizontal shaft 38. The shaft 38 is operatively driven from an electricmotor M through a gear reduction device 46 in the form of a conventionalspeed change transmission having a control handle 48 by means of whichthe speed ratio drive may be varied at will. It will be seen, therefore,that the brick feed conveyor and the rotary drum 14 are operativelyconnected in driving relationship for movement in unison for purposesthat will be made clear presently. The lower front end of the conveyor10 which embodies the driven sprocket wheel 30 is operatively supportedon standards or posts 50 forming a part of the conveyor framework.

The various link components 32 are identical and each includes acarriage 52 which is slidable on the conveyor rails 33 (see FIG. 5) andfrom the lower end of which there depends a lug 54. A downwardlyextending swinging tray-supporting arm 56 is pivotally connected at itsupper end to each of the lugs 54 and the lower end of the arm servesremovably to support one of the composite articulated brick-supportingand transporting trays 18. One of the articulated brick-supporting andtransporting trays 18 is illustrated in detail in FIGS. 10 and 11 andwill be fully described presently.

Swinging movements of the tray-supporting arms 56 are restrained andlimited by means of a series of curved hook-like fingers 62 which areconnected to and depend from the carriages 52, cooperate with fixedlaterally extending pins 64 on the medial regions of the arms 56, andlimit the extent of swinging movement of the arms in one direction. Thepins 64 are also designed for cooperation with fixed cam rails 66 and 68which are positioned in their path of movement, the cam rail 66 beingpositioned ahead of the cam rail 68 and underlying the inner region ofthe horizontal rear end of the feed conveyor, and the cam rail 68 beingdisposed above the drum 14. The cam rail 66 serves to retract or swingupwardly the various arms 56 as they approach the transfer station T andcause the trays 18 that are supported thereby to make accurate registerwith the series of articulated brick-receiving and transporting cradles20 which are mounted on the periphery of the drum 14 and arrive at thetransfer station T in correlation with the trays 18. The cam rail 68extends horizontally and serves to elevate the trays 18 after they havedischarged their respective bricks and deposited them in the cradles 20.

The effective diameter of the drum 14, the effective diameter of thedriving sprocket wheel 29, and the gear ratio drive which obtainsthrough the gear box 44 are such that precisely at the time that one ofthe cradles 20 arrives at the transfer station T, a tray 18 arrives atthis station to transfer its brick to the subjacent cradle 20. The trays18 arrive at the transfer station T in a closed condition, while thecradles 20 arrive at the transfer station in an open condition. Toeffect the transfer of bricks from the trays 18 to the cradles 20,interengaging means on the trays 18 and the cradles 20 become effectiveto cause the trays 18 to become open so that the latter discharge theirbricks by gravity into the cradles 20. At substantially the same timethat the trays 18 become open, interengaging means on the cradles 20 anda fixed portion of the drum framework become eflective to close thecradles upon the deposited bricks in order thus securely to clamp thebricks and conduct them in succession to the grinding station where theyare rigidly held during passage thereof between the two spaced apartgrinding wheels 25.

The articulated brick conveying trays 18 Referring now to FIGS. 1, 2,and 11,. each of the brick transporting trays 18 involves in its generalorganization a crosshead 100 from which there projects laterally fromone side thereof a central spindle 102. From the other side of thecrosshead 100, there project laterally two spaced apart jaw-supportingspindles 104 and 106 and they carry opposed brick-confining jaws 108 and110, respectively. The two opposed jaws 108 and 110 depend from thespindles 104 and 106 and are movable back and forth between the openposition in which they are shown in dotted lines in FIG. 10 and theclosed full-line position thereof. The lower end of each jaw carries ashelf-like tray section 112 including a bottom wall 114, a side wall116, and an end wall 118. When the two jaws 108 and 110 of each tray 18are in their closed position, the bottom walls 114 of the tray sections112 are adapted to underlie the side edges of a brick which is supportedwithin the tray 18 with the brick being supported by gravity upon suchbottom walls and with the end walls 118 abutting or at least in registerwith the trailing end wall of the brick. In the open position of eachtray wherein the jaws 108 and 110 are in their open position, the twotray sections 112 clear the lower side edges of the brick so that thelatter. may fall by gravity from the tray and be thus transferred to acooperating cradle at the transfer station T in a manner that will bemade clear presently.

Normally, the jaws 108 and 110 of each tray 18 are yieldingly maintainedin their open position by a helical tension spring 120, the ends ofwhich are connected by links 122 to upstanding lugs or extensions 124 onthe two opposed jaws 108 and 110. A horizontally extending limit stopbar 126 is secured to the crosshead and has its ends designed forengagement with additional extensions 128 on the two jaws. The bar 126and the extensions 128 coact to determine the fully open position of thetwo jaws.

Meansyare provided for releasably latching the jaws 108 and of each tray18 in their closed position, such means comprising a pair of inwardlyextending oppositely directed latch arms 130 and 132 on the jaws 108 and110, respectively. The latch arm 130 is pivoted as at 131 to the jaw 108and is formed with a hook portion 134 which is designed for latchingengagement with a horizontally and laterally extending latch pin 136 onthe latch arm 132 when the jaws are in their closed position. Adepending guide shoe 138 is formed on the latch arm 130 and has a guidesurface 140 which is designed for engagement with the latch pin 136 andserves to guide the same into the hook portion 134 during closingmovement of the two jaws 108 and 110.

In order to stabilize the movements of the two jaws 108 and 110 of eachtray so that when the jaws are in their closed position, the bricks thatare carried thereby will be centered beneath the crosshead 100, twosubstantially horizontal toggle links 142 are provided. The toggle linksextend outwards in opposite directions and have their outer endspivotally connected to short extensions or lugs 143 on the jaws 108 and110, respectively. The inner ends of the toggle links are pivotallyconnected to the.

ends of a substantially vertical toggle bar 144 which is pivotedmedially of its ends as at 146 to the crosshead 100. The toggle links142 are of equal efiective length and serve to equalize the movements ofthe two jaws 108 and 110 during opening and closing thereof.

The guide shoe 138 of each tray 18, in addition to guid-. ing the pin136 into latching engagement with the hook portion 134 of the latch arm13%, also serves as a trip element for releasing the latch means ormechanism which holds the two jaws 108 and 110 in their closed position.In such capacity as a trip element, the guide shoe 138 is adapted to beengaged by a cooperating trip finger 148 in associated relation with oneof the cradles 20 at such time as the tray 18 arrives at the transferstation T so that the tray will assume its open position and dischargethe brick carried thereby to the cooperating or underlying cradle 20,all in a manner that will be made clear when the nature of the drum 14and its associated brick-conveying cradles 20 is better understood.

The lower ends of the two jaws 108 and 110 of each tray 18 carry ontheir outer side portions individual rollers 150, the latter beingrotatably supported in brackets 152 which are suitably secured to thejaws and project outwards therefrom. The rollers are designed forcamming engagement with two converging rail sections 154 which aresuitably supported on a fixed base 155 (see FIG. 1) adjacent to thereceiving station R. As the open trays 18 successively approach thereceiving station R as shown at the left-hand side of FIG. 1, therollers 150'enter between the two rail sections 154, thus forcing thelower ends of the jaws 108 and 110 inwardly toward each other to closethe jaws and cause the latch arms 130 and 132 to become engaged andmaintain the trays in their closed condition preparatory to receivingbricks at the receiving station R. It is contemplated an operator willbe stationed at the station R and that he or she will manually placebricks in the closed trays as they move successively past said station.

THE GRINDING MACHINE PROPER The drum 14 Referring now to FIGS. 5, 6 and7, the grinding machine proper 12 includes the drum 14, the centeringdevice 24, and the grinding stand 26. The drum 14, as previously stated,is generally of cylindrical or disc-like design and is supported uponthe horizontal shaft 38 which is rotatably mounted in the bearings 40 onthe masonry base 36. It comprises a pair of spaced apart generallycircular side plates 200 having formed therein access opening 202 whichare normally closed by means of removable cover plates 204 (see FIG. 6).A cylindrical peripheral wall 201 (see FIG. 7) extends between the twoside plates 200. An annular series of radial gusset webs 206 in thecentral region of each side plate 200 serves to reinforce and strengthenthe side plate. The various articulated brickreceiving and transportingcradles 20 are mounted on the periphery of the drum 14 at equally andcircumferentially spaced regions therearound, eight such cradles beingdisclosed in the illustrated form of the invention, although it will beunderstood that a greater or lesser number of such cradles may beemployed if desired. Articulation of these cradles is effected under thecontrol of an hydraulic system which subsequently will be described andthe details of which are illustrated in FIG. 8. For the present, it isdeemed sufiicient to state that this hydraulic system includes a seriesof eight piston and cylinder assemblies 210, one for each cradle, aseries of eight directional control valves 212, one for each piston andcylinder assembly, and a series of eight high pressure accumulators 214,one for each piston and cylinder assembly. An additional low pressureaccumulator 216 is also included in the aforementioned hydraulic systemand the function of such accumulator will be made clear presently. Allof these hydraulic instrumentalities, together with the piping and otherfluid connections therefor, are operatively installed on the drum andassume positions within the space existing between the two side plates200.

The articulated brick conveying cradles 20 and actuating means thereforStill referring to FIGS. 5, 6 and 7, wherein the details of thearticulated brick-supporting and conveying cradles are best shown, thevarious cradles 20 are removably mounted on the periphery of the drum 14and each cradle involves in its general organization two side plates 220which straddle the drum and are connected by bolts 222 to the drum sideplates 200. The two side plates 220 of each cradle are identical and theleading end regions thereof are formed with fixed substantially radiallyextending fingers 224, the outer ends of which have pivoted theretospider-like jaw elements I225. Each jaw element is provided with a pairof outwardly divergent members at the outer ends thereof havingresilient brick-engaging clamping strips 226?. So far :as each cradle 20is concerned, the jaw elements 225, together with the radially extendingfingers 224, constitute, in effect, a fixed composite reaction jaw 227that is designed for engagement with the leading region of a brick inthe cradle. The outer edges 22% of the side plates 220 of each cradleare linearly straight and constitute, in effect, a cradle bottom onwhich a brick, such as the brick shown at B in FIG. 7, is adapted to besupported with the brick bridging the distance between the two sideplates and overhanging the latter at the sides thereof. Each cradle alsocomprises a composite movable jaw 260 in the form of two side arms 232,the inner ends of which are pivoted on a pin 234. The latter extendsbetween the side plates 226 and supportsthe movable jaws 230 so that itis capable of swinging movement toward and away from the fixed jaw 227between open and closed positions as shown in full and dotted linesrespectively in FIG. 6. The outer ends of the side arms 232 are providedwith pivoted jaw elements 235 which are substantially indentical withthe jaw elements 225.

The inner ends of the side arms 232 of each movable cradle jaw 230 areprovided with extensions 236 the distal ends of which are provided withlongitudinally extending slots 238. These extensions 236 constituteactuating levers for each movable jaw 230 and the slots 23S receivetherein horizontally extending pins 240 which are connected to andextend outwards from the distal ends of a pair of arms 242. Each pair ofarms 242 is mounted on a horizontal rock shaft 244 which extends between=and through the side plates 260 of the drum 14. A crank arm 246 has oneend thereof fixedly secured to each rock shaft 244. The other ends ofthe crank arms 246 are pivotally connected to plungers 248 which arefixedly connected to the pistons of the piston and cylinder assemblies210. The cylinder 250 of each piston and cylinder assembly 216 ispivot-ally connected at one end thereof to the drum 14- by means of ahorizontally extending cross shaft 252 which extends between the twodium side plates 200.

From the above description, it will be seen that when the plungers 248are retracted Within the cylinders 251 as shown in full lines at theleft-hand side of FIG. 6, the movable jaws 230 will assume theirretracted position wherein the cradles 20 may be said to be in theiropen condition. When the plungers are in their extended dotted-lineposition as shown at the left-hand side of FIG. 6 and as shown in fulllines at the righthand side of this view, the movable jaws 230 will beswung toward the fixed jaws 224 for brick-clamping purposes and eachcradle 20- may be said to be in its closed condition.

Hydraulic control of the articulated cradles 20 Referring now to FIG. 8of the drawings, a fixed source 300 of fluid under pressure communicatesthrough leadout and return lines 302 and 304 with first and secondpressure chambers 306 and 308, respectively. These pressure chambers arein the form of relatively deep sockets which are formed in the ends ofthe rotary drum-supporting shaft 38. The connections between the lines302 and .304 and the pressure chambers 306 and 308 are effected by meansof suitable rotary mechanical seals 310.

A local hydraulic control circuit is provided for each of the eightcradles 24 one of the eight circuits being schematically illustrated inFIG. 8. This circuit extends from the pressure chamber 306 through afluid line 312 to one of the directional control valves 212 through theinlet port 314 thereof. This valve 212 is in the form of a three-waydirectional valve in which the movable valve element 316 thereof iscapable of selectively assuming three different positions under thecontrol of an actuating finger 318. These three positions are labelled1, 2 and 3 in FIG. 8 and include :a first or #1 position wherein theinlet port 314 is connected to a common port 328-; a second or #2position wherein the common port 320 is closed; and a third or #3position wherein the common port 320 is connected to :an outlet port322.

The common port 320 is connected through a line 324 to one end of one ofthe cylinders 250 of one of the piston and cylinder assemblies 219. Theother end of the cylinder 250 is connected through a branch fluid line626 to a distribution manifold 328. The fluid line 324 is connectedthrough a three-way fitting or T 329 to one of the pressure accumulators214. The distribution manifold 328 is connected through a single fluidline 334) to the pressure chamber 306 and a pressure regulator 332 isinterposed in the line 330. The outlet port 322 of the valve 212 isconnected through a fluid line 334 to the pressure chamber 308. Themanifold 328 also is connected to the pressure chamber 30-3 through asingle fluid line 336 having a pressure regulator 338 interposedtherein. The distribution manifold 328 is fed by the single pressureaccumulator 216 through a line 340.

It is to be noted in connection with the hydraulic oircuit diagram ofFIG. 8 that two broken line polygonal enclosures appear in this view.These enclosures are designated at A and B, respectively. All of thecomponents which are included within the enclosure A are eig-htfoldcomponents, there being one for each cradle 20. The components which areincluded in the rectangle B are single components.

Hydraulic timing cam controls Referring again to FIG. 5, the variousactuating fingers 318 of the eight directional control valves 212, infollowing their common circular path of movement during rotation of thedrum 14 make successive engagement with three circumferentially spacedfixed control cams 350, 352 and 354. These fixed control cams arefixedly mounted on a suitable support (not shown) and are disposedexteriorly of the drum 14 and in the path of movement of the variousactuating fingers 318. Said support preferably constitutes a portion ofthe drum-supporting framework.

The cam 351} constitutes a cradle-closing cam inasmuch as when one ofthe actuating fingers 318 engages it, the associated directional controlvalve 212 is actuated in such a manner as to institute closing movementsof its respective or associated articulated cradle 20. This cam is sopositioned with respect to the drum that it will be engaged by one ofthe actuating fingers 318 at approximately the time that its associatedopen cradle arrives at the transfer station T and receives a bricktherein by deposition from one of the trays 13.

The cam 352 is so positioned with respect to the drum that it will beengaged by one of the actuating fingers 318 at approximately the timethat its associated closed cradle 2t) arrives at the centering stationC. Its function at this 1 1 time is to actuate the adjacent directionalcontrol valve 212 in such a manner that holding fluid under pressure isapplied to the movable jaw 230 of the associated cradle, such holdingfluid under pressure being supplied by the associated high-pressurepressure accumulator 214.

The cam 354 is a cradle-opening cam and is so positioned with respect tothe drum 14 that it will be engaged by one of the actuating fingers 318at approximately the time that its associated cradle 20 arrives at thedischarge station D. Its function is to actuate the adjacent directionalvalve 212 in such a manner as to institute cradleopening movements tothe end that the brick which has been operated upon at the grindingstation G and is carried by the cradle 20 will be discharged by gravityonto the discharge conveyor 16.

To attain the above-stated aims, the control cam 350, when engaged byone of the actuating fingers 318, serves to move the movable valveelement 316 of the associated directional control valve 212 to itspreviously described first position, so labelled in FIG. 8. When engagedby an actuating finger 318, the control cam 352 serves to move theassociated movable valve element 316 to its second position. Whenengaged by a finger 318, the third control cam 354 serves to move thevalve element 316 to its third position.

The hydraulic functions which take place with the eight movable valveelements 316 in their respective aforementioned first, second and thirdpositions will be set forth in detail subsequently when the operation ofthe subject brick grinding apparatus is set forth hereafter.

The centering device 24 The centering device 24 is disposed at thecentering station C and is provided for the purpose of centering thebricks which have been transferred to the cradles 20 from the trays 18so that their center lines will lie in the medial plane of the drum 14,and what is more important, so that they will become circumferentiallyaligned with the medial plane passing between the two grinding wheels 25at the grinding station G. With the bricks thus centered, the abrasivework performed by the grinding wheels will be equalized and each wheelwill remove an approximately equal amount of material from the faces ofthe bricks on which it operates.

The centering device 24 is best illustrated in FIGS. 5 and 12 and thehydraulic control circuit by means of which it is actuated is shown inFIG. 9. Referring now to FIG. 5, the centering device 24 is carried on alaterally projecting shelf 360 which, in turn, is supported from theaforementioned vertical posts 35. The device 24 includes a support inthe form of an outer housing or casing 362 which is of rectangularbox-like design and within which there is disposed a pair of oppositelydisposed coacting pivoted rocker arms 364 and 366 (see FIG. 12). Certainopposed end portions of the rocker arms are pivoted on spaced apartvertically extending pins 370 and 372,re spectively, in order that theyare permitted to swing towards and away from each other under thecontrol of a piston and cylinder assembly 374. The latter comprises ahorizontally disposed cylinder 376 which is pivoted at one end to therocker arm 364, and a plunger 378 which has one end thereof connected tothe piston of the assembly 374 and its other end pivoted to the rockerarm 366. The movements of the two rocker arms are equalized by means ofa pin and slot connection 380 which exists between laterally extendinglugs or extensions 380 and 382 on the rocker arms 364 and 366,respectively. The proximal ends of the rocker arms 364 and 366 haveconnected thereto jaw extensions 384 and 386 and they carry at theirouter ends the previously mentioned centering shoes 22 which oppose eachother on opposite sides of the drum 14 and are designed for centeringengagement with the adjacent opposite faces of successive bricks passingthrough the centering station C and carried by the cradles 20. The shoes22 are provided with resilient lining strips 12 392. A helical tensionspring 394 is connected at its ends to the two rocker arms 364 and 366,thus drawing these two arms together to retract the plunger 378 andspread the centering shoes 22 apart so that they assume their fully openposition for entry of the successive bricks.

therebetween.

Hydraulic control circuit for actuating the centering device 24Referring now to FIGS.5 and 9, the centering device 24 is operable underthe control of a directional reversing valve 400 which is suitablyfixedly supported in the path of movement of a series of eight trip cams402. The lat-.

ter are positioned in circumferentially spaced relationship on one ofthe side plates 200 of the drum 14, there being one trip cam 402 foreach of the cradles 20. Said trip cams 402 are designed for engagementwith a pivoted actuating finger 404 in associated relation with thedirec-v tional reversing valve 400.

The valve 400 is a simple two-way reversing valve in which the movablevalve element 406 thereof is capable of assuming first and secondpositions, labelled, respectively, 1 and 2 in FIG. 9. The movable valveelement 406 and the actuating finger 404 are spring-biased to the normalfirst position wherein fluid under pressure is permitted to flow from asump 408 through a fluid line 410, a motor-driven pump 412, a line 414,the valve element 406, and a line 416 to one end of the cylinder 376 ofthe centering device 24 in order to retract the plunger 378 (see FIG. 9)and thus maintain the centering shoes '22 in their spaced apart or openrelationship. During move.

ment of the plunger 378 to its retracted position, fluid under pressureis returned to the sump 408 by way of a fiuid line 418, the valveelement 406 and a line 420. Such.

movement of the plunger is assisted by the action of the aforementionedhelical spring 394. I

Upon engagement of the actuating finger 404 of the directional reversingvalve 400 by one of the trip cams 402, the movable valve element 406will be moved to its second position and fluid under pressure will flowfrom p the sump 408, through the line 410, the pump 412,,the

line 414, the movable valve element 406, and the. line 418 to the otherend of cylinder 376 to extend the plunger 378 and thus cause thecentering shoes 22 to close upon and the centering shoes 22 is of butslight duration, the

centering shoes 22 serving merely to tap, so to speak,

the adjacent opposite faces of the adjacent brick, thus causing thebrick to slide sidewise with respect to the drum 14, the clampingelements on the pivoted jaw elements 225 and 235 of the adjacent cradleallowing such sidewise movement of said adjacent brick so that it willbe brought into centered relationship with the medial plane of the drum14 and into circumferential alignment with the grinding wheels 25 aspreviously described. After the centering operation, the two centeringshoes 22 return to their normal widely separated position, thusreleasing the adjacent centered brick for passage to the grindingstation G.

The grinding stand 26 Referring now to FIGS. 1 and 3, the grinding stand26 at the grinding station G includes a fixed base support 450, theupper face of which provides an elon gated dovetail guideway 452 withinwhich there is slidably disposed a pair of mounting carriages 454 and456. The carriage 454 has mounted thereon a bearing support 458 for thehorizontal drive shaft 460 of one of the two spaced apart grindingwheels 25, while the carriage 456 has mounted thereon a similar bearingsupport 462 for the horizontal drive shaft 464 of the other grindingwheel. The carriage 454 further serves to support an electric motor M1which is operatively connected in driving relationship to the driveshaft 460 by way of a belt 13 and pulley arrangement 466. The othergrinding wheel 25 is similarly driven from an electric motor M2 on thecarriage 456.

The two carriages 454 and 456 are capable of horizontal adjustmenttoward and away from each other to vary the effective distance betweenthe two grinding wheels 25 and, accordingly, these two carriages areoperatively connected together by way of an elongated horizontallyextending worm shaft 48% which has its medial portions supported in abearing block 482 and embodies oppositely threaded end portions 484 and486. The latter are threadedly received in the bearing supports 458 and462, respectively. The worm shaft 48% is provided with a hand wheel 490by means of which it may be manually turned in either direction to varythe distance between the two carriages 454 and 456, and consequently,between the operative working faces of the two grinding wheels 25.

The grinding stand 26 is so positioned with respect to the drum 14 thatthe two grinding wheels 25 are centered with relation to the medialplane of the drum, which is to say,'that the respective and effectivegrinding planes of the two grinding wheels 25 are equally spaced onopposite sides of the medial plane of the drum.

If desired, there may be additional pairs of powerdriven grinding wheelsat the grinding stand 26. If, for example, there are two pairs ofgrinding wheels, the wheels of the first brick-encountered pair may beconstructed to effect a quick coarse grind and the wheels of the secondbrick-encountered pair may be designed or constructed to produce a finegrind.

OPERATION OF THE APPARATUS The operation of the herein described brickgrinding apparatus will be facilitated by reference to FIGS. 13 and 14in conjunction with the other views of the drawings, particularly FIGS.1 and 5. The disclosure of FIGS. 13 and 14 is purely schematic, littleattention to the specific details of the feed conveyor and the drumbeing given. In these views, the positional relationship between thefeed conveyor and the grinding machine proper 12 including the drum 14and the grinding wheels 25 has been illustrated with particularreference to the positional relationship of a representative brick Bundergoing treatment in the apparatus, this brick being of enlargedproportions and disposed above its path of travel along the feedconveyor 10. 7

According to the present invention, an operator such as theoperator O ofFIG. 1 will be positioned at the receivingstation R for the purpose offeeding the bricks B, one at a time, to the successive trays 18 passingthrough this station. The trays 18 having, as previously described, beenoperated upon by the converging rail sections 154 immediately prior totheir entry into the receiving station R, are in their closed conditionat the time they arrive at the receiving station in order that thebricks may be placed upon the bottom walls 114 of the tray sections 112and caused to rest thereon with the bricks being loosely confinedbetween the opposed side walls 116 as best shown in FIG. 10.

The exemplary brick B that is shown in triplicate and in enlarged formin FIG. 13 is in the form of a hexahedron of generally rectangulardesign and has a long dimension or length I, an intermediate lengthdimension or width w, and a short dimension or height h. The brick B isshown in each of three positions of orientation which it assumes forthree successive passes through the apparatus. In the oriented positionof the brick shown in this view for the first run, the. brick resentsupper and lower side faces a and b, side faces cand d, and end faces eand f.

In order accurately to grind the various faces of each brick B to trueplanar condition and rectangular proportions, it is necessary to conducteach run of bricks through the apparatus three times, the first passserving to condition the side faces 0 and d, the second pass serv- 14ing to condition the side faces a and b, and the third pass serving tocondition the end faces 2 and 1.

During the first pass, the bricks B will be successively placed by theoperator 0 in the trays 18 and with the bottom side faces b resting onthe bottom walls 114 of the tray sections 112 and with the end faces eleading the trailing end faces 7 in the direction of movement of thetrays from the receiving station R to the transfer station T. The bricksB will progress along the feed reach section 27 of the feed conveyor 10in the manner indicated in FIGS. 1 and 14 and arrive at the transferstation T in an approximately horizontal position.

Due to the correlated drive between the feed conveyor 10 and the drum14, simultaneous arrival of the brickcontaining trays 13 and the emptycradles 20 at the transfer station T will take place, a closedbrick-laden tray 18 on the feed conveyor 10 overlying an open emptycradle 29 on the drum 14. Precise timing movements are maintained sothat substantially at the time that this superposed relationship betweena particular tray and a particular associated cradle obtains, theupstanding trip finger 148 that is associated with the cradle willengage and move upwards the superjacent guide shoe 133 on the particulartray (see FIG. 10), thus releasing the cooperating interlocked latcharms 130 and 132 and allowing the spring 120 to open the jaws 108 and ofsaid particular tray, thus releasing the brick and causing the same tobe deposited in the associated open cradle 20 therebeneath. Thistransfer of a brick from one of the trays 18 to an associated orcooperating cradle 20 is best illustrated in FIG. 5 in the upper centralregions of this view.

As soon as the aforementioned brick B has been deposited in theaforementioned particular cradle 20,the associated valve-actuatingfinger 318 will move into engagement with the fixed control cam 350 (seeFIG. 5), thus actuating the associated directional control valve 212(see FIGS. 6 and 8) in such a manner as to supply fluid under pressureto the associated cylinder 250 and extend the plunger 248 of theassociated piston and cylinder assembly 210 in such manner that theassociated crank arm 246 is actuated in a direction to swing the movablejaw member 239 toward the fixed reaction jaw 227 and clamp the brick Btherebetween.

Actual brick seizure by the two composite jaws 230 and 227 of eachcradle 20 is effected by the pivoted spider-like jaw elements 235 and225 each of which straddles an upper transverse edge of the brick withone corresponding set of resilient clamping strips 226 engaging theupper face a of the brick and with the other set of correspondingresilient clamping strips 226 engaging the leading and trailing verticalend faces e and f of the brick. Such engagement of the brick isillustrated in FIG. 5 wherein the five cradles 2G existing at andbetween the centering station C and the discharge station Dare shown asbeing in their closed brick-clamping position.

Bricks issuing from the kiln are posssessed of numerous irregularities.Frequently, the side faces of a brick are non-rectangular; oppositefaces are out-of-parallel; adjacent faces are at either obtuse or acuateinclinations; the faces are non-planar; and burrs and otherirregularities are present on the various faces of the brick,particularly along the edge regions of the brick. The pivoted spiderlikejaw elements 235 and 225 insure firm gripping of a given brickirrespective of such abnormal shape characteristics.

From the transfer station T, the cradles 20 move toward the centeringstation C, while at the same time, the trays 18 are swung to anout-of-the-way position by means of the cam rail 68 which issuccessively engaged by the laterally extending pins 64 on thesupporting arms 54. As soon as a given cradle 20 arrives at thecentering station C, a corresponding trip earn 402 (see FIG. 5) engagesthe actuating finger 404 of the reversing valve 400 (see FIG. 9) andactuates the valve in such a manner that fluid under pressure isconducted to the cylinder 376 (see also FIG. 12) to extend the plunger378 and effect closing movements of the two centering shoes 22 in themanner previously described. The centering shoes 22 engage the adjacentopposite faces of the brick and center the brick with respect to themedial plane of the drum 14, thus circumferentially aligning the brickwith the two grinding wheels 25 at the grinding station G. As soon asthe aforementioned trip cam 402 releases the actuating finger 404, thelatter is restored to its normal position and the centering shoes 22automatically return to their positions of max'unum separation.

The thus centered bricks are then conducted past the grinding station Gwhere they pass between the two grinding wheels 25 and have theiradjacent opposite faces operated upon by the opposed planar circularsurfaces of the grinding wheels. Due to the centering action which isefl'ected immediately prior to arrival of the bricks at the grindingstation, the work that is performed by the two grinding wheels will besubstantially equalized with neither adjacent brick face presenting anundue amount of grinding wheel overhang suflicient to cause damage toeither the grinding wheels or the bricks.

It is to be noted at this point that at such time as a particular cradle20 arrives at the centering station G, the actuating finger 318 of theassociated directional control valve 212 has moved out of engagementwith the control cam 350 and into engagement with the control cam 352(see FIG. This latter control cam serves to move the finger 318 in suchmanner as to shift the movable valve element 316 of said associatedvalve from its #1 position to its #2 position as labelled in FIG. 8. Inthe #2 position of the element 316, the pressure accumulator 214 servesto supply holding fluid under pressure to the cylinder 250 as previouslydescribed to maintain jaw pressure on the faces of the brick which isdisposed within the aforementioned particular cradle 20. This positionof the valve element 316 is maintained throughout the remainder of thetravel of the brick through the apparatus and until such time as theactuating finger 318 engages the cradle-opening control cam 354 when thecradle is at the discharge station D.

During the first pass of each brick B through the grinding station G,the opposite side faces c and d of the brick will encounter the opposedinside faces of the two spaced apart grinding wheels 25 as schematicallyportrayed in FIG. 14 and be rendered smooth, planar and preciselyparallel irrespective of any irregularities or lack of parallelismexisting in or between the four faces a, b, e and which are engaged bythe pivoted spider-like jaw elements 235 and 225. During the actualgrinding operation, the resilient clamping strips 226 allow the brick toassume a floating condition between the two grinding surfaces, eachsurface serving as a reaction surface for the other. Each brick, withits two faces c and d thus conditioned, is conducted by cradle 20 fromthe grinding station G to the discharge station D where the actuatingfinger 318 of the associated directional valve 212 encounters the fixedcontrol cam 354, thus causing the movable valve element 316 (see FIG. 8)of said associated directional valve 212 to move to its #3 position andeffect retraction of the plunger, 248 so as to open the cradle :andrelease the brick so that it drops onto the upper reach of the endlessdischarge conveyor 16.

The bricks which comprise the first run of bricks and have their sidefaces 0 and d conditioned in the manner indicated above, may now bereturned to the receiving station R where they are again individuallyand successively loaded upon the trays 18 of the feed conveyor 10 for asecond run through the apparatus. During this second run, the grindingwheels operate upon the faces a and b as schematically shown in FIG. 16.To accommodate placement of the bricks in the trays 18 of the feedconveyor 10 so that proper brick orientation in the trays 18 with thefaces 0 of the bricks now constituting the leading faces, trays havingdimensions or shapes which are commensurate with the interchangeddimensions of the bricks will be substituted for the original trays 18..

This substitution of trays may readily be accomplished by removing thespindles 102 and their associated original trays from the lower ends ofthe downwardly extending swinging supporting arms 56 of the feedconveyor 10 and re-applying the spindles of the substitute trays. It mayalso be necessary to effect substitution of the various cradle 20 on thedrum 14 in order to accommodate the differently oriented bricks B. Thismay readily be accomplished by proper manipulation of the fasteningbolts 222. Additionally, the spacing between the two grinding wheels 25may be altered in the manner previously described to accommodate thedifferent transverse dimension of the bricks during the second run orpass.

It is to be noted that when the bricks are loaded .for

the second time on the trays 18 of the feed conveyor 10 1 with theirfaces 0 constituting the leading faces and the faces d constituting thetrailing faces, these two faces will likewise constitute the leading andtrailing faces of the bricks after the transfer has been made at thetransfer station and the bricks are carried in the cradles 20 of the'drum 14. Since these faces a and d are ones which were rendered planarand parallel during the first run, they will now constitute accuratereference faces for clamping engagement by the jaws 230 and 227 of thevarious cradles 20. V

The substitute cradles employed during the second run of bricks throughthe apparatus are, in essence and other than shape and dimensions,substantially the same as the original cradles 20 employed during thefirst run of bricks with the single exception that the pivotedspider-like jaw elements 235 and 225 may be omitted and the leading andtrailing faces 0 and d of the bricks clamped directly in the cradlesbetween the jaws 230 and 227, the endfaces of the bricks bearingdirectly against'the inside edge of the upstanding jaw fingers 224 ofthe fixed jaws 227,and the jaw side arms 232 of the removable jaws 230.

After the bricks have been subjected to their second 1 run and depositedon the discharge conveyor 16 with their faces a and b accurately groundso that they are precisely parallel and normal to the. previously groundfaces o and d, they are returned to the receiving station R for a thirdrun or pass through the apparatus. During this third run of bricks, thebricks will be fed to the trays 18 of the feed conveyor 10 withrthefaces 0 constituting the d and the grinding wheels 25 will operate uponthe end faces e and f of the bricks as schematically shown "in FIG. 17.The bricks which are discharged upon the conveyor 16 during the thirdrun of bricks will have all of their six faces not only planar within ahigh degree of flatness, but these faces will all be truly rectangularwith opposite faces beingparallel to each other and with the bricksbeing devoid of burrs and other irregularities.

The invention is not to be limited to the exact arrangement of partsshown in the accompanying drawings 1 or described in this specificationas various changes in the details of construction may be resorted towithout'de parting from the spirit or scope of the invention.

run of bricks through the apparatus, it is contemplated that three ofthe apparatuses may be arranged in sideby-side or series relation withthe receiving station of the second apparatus being positioned adjacentto the discharge station of the first apparatus, and with the re ceivingstation of the third apparatus being positioned adjacent to thedischarge station of the second apparatus.

For example, whereas the treatment of bricks for the con- 5 ditioning ofall six faces thereof has been described as being predicated uponeffecting three passes of a given The various trays 18 and the cradles20 of the three apparatuses will be constructed to accommodate thedimensional characteristics and orientation of the bricks of the threeruns of bricks, while the spacings between the grinding wheels 25 of thethree grinding stands 26 will also be commensurate with the spacingbetween the adjacent opposite faces of the bricks being operated upon byeach pair of grinding wheels.

The invention is not to be understood as restricted to the particulardetails set forth since these may be modified within the scope of theappended claims without departing from the spirit and scope of theinvention.

Having thus described the invention what I claim as new and desire tosecure by Letters Patent is:

1. In a brick grinding apparatus for conditioning pairs of oppositefaces of bricks, in combination, means establishing a receiving station,a transfer station, a grinding station and a discharge station, a feedconveyor having a fixed framework and including a series ofbrick-supporting trays movable in feed and return relation between thereceiving and transfer stations and adapted to receive a succession ofbricks at the former station and transfer them to the latter station, abrick-clamping conveyor having a fixed framework and including a seriesof brickclamping cradles movable in advance and return relation betweenthe transfer and grinding stations and adapted to receive the bricksfrom the feed coveyor at the transfer station and conduct them to thegrinding station, a pair of grinding wheels at the grinding station andhaving opposed grinding surfaces between which the clamped bricks in thecradles are adapted to pass, each tray including a pair of tray sectionsmovable between closed brick-supporting and open brick-releasingpositions, spring means yieldingly urging said tray sections towardtheir open positions, latch means automatically operable to maintain thetray sections in their closed position against the action of said springmeans, cam means operable during the return movements of the trays formoving said tray sections to their closed position, each cradleincluding a pair of brickclamping jaws movable between closedbrick-clamping and open brick-releasing positions, means for moving saidconveyors in timed relation so that'the trays and cradles arrive inmatched pairs at the transfer station, means operable upon arrival ofeach tray at the transfer station to trip the latch means thereof toopen the tray sections and release the brick supported thereby, meansoperable upon arrival of each cradle at the transfer station to closethe jaws thereof in order to clamp therebetween a brick released fromthe feed conveyor, and means operable upon arrival of each cradle at thedischarge station for opening the jaws thereof to release the groundbricks.

2. In a brick grinding apparatus, the combination set forth in claim 1and wherein said means for tripping the latch means of the trays at thetransfer station comprises interengaging latch-tripping fingers on thecradles and trays and movable into engagement with each other as thematched pairs of cradles and trays arrive at the transfer station.

3. In a brick grinding apparatus, the combination set forth in claim 2and wherein the lower end of each jaw is provided with a shelf-likesupporting tray adapted to underlie one edge region of a brick which ispositioned in the associated cradle.

4. In a brick grinding apparatus, the combination set 6. In a brickgrinding apparatus, the combination set 1'8 forth in claim 1 and whereinsaid cam means for moving said tray sections to their closed positionincludes a cam rail on the framework of the feed conveyor andsuccessively engageable with the tray sections during return movement ofthe trays.

7. In a brick grinding apparatus, the combination set forth in claim 1,wherein said means for tripping the latch means on the trays at thetransfer station comprises interengaging latch-tripping fingers on thecradles and trays and movable into engagement with each other as thematched pairs of cradles and trays arrive at the transfer station,wherein the means for closing the jaws of the brick-clamping cradlescomprise a jaw-actuating linkage connected to each pair ofbrick-clamping jaws and including an actuating finger, and a jaw-closingtrip'cam fixedly mounted on the framework of the brick-clamping conveyorand positioned in the path of movement of the successive actuatingfingers, and wherein the means for opening the jaws of thebrick-clamping cradles comprises a jaw-opening trip cam fixedly mountedon the framework of the brick-clamping conveyor and likewise positionedin the path of movement of the successive actuating fingers.

8. In a brick grinding apparatus for conditioning pairs of oppositefaces of bricks, in combination, means establishing a transfer station,a grinding station and a discharge station, rotatable grinding wheels atsaid grinding station and having opposed operative surfaces, a rotatabledrum having peripherally spaced cradles movable successively through thetransfer station to receive bricks therein, the grinding station tocarry the bricks between said opposed operative surfaces of the grindingwheels, and the discharge station to discharge the conditioned bricksthereat, each cradle including a fixed reaction jaw and a movableclamping jaw movable between an open brick-releasing position and aclosed brick-clamping position wherein it engages one end face of abrick and forces the opposed end face against the fixed reaction jaw,each fixed and movable jaw including a pivoted jaw element directlyengageable with the brick and embodying a pair of diverging yoke armsadapted to straddle an adjacent transverse ege of the brick with one armbearing against an adjacent face of the brick and the other arm bearingagainst an adjoining face of the brick, a fluid pressure device mountedon the drum and connected to each movable clamping jaw, a control valvefor each fluid pressure device, mounted on the drum and having a controlfinger effective in one position thereof to actuate the fluid pressuredevice so as to effect closing of the associated movable clamping jawand effective in another position to actuate the fluid pressure deviceso as to effect opening of the clamping jaw, a fixed jaw-closing campositioned in the path of movement of said control fingers and effectivewhen engaged by the latter to move the same to said one position, afixed jaw-opening cam positioned in the path of movement of said controlfingers and elfective when engaged by the latter to move the same tosaid other position, said jaw-closing cam being engageable by saidcontrol fingers when the associated cradles are disposed at the transferstation, said jaw-opening cam being engageable by said control fingerswhen the associated cradles are disposed at the discharge station, asource of fluid under pressure for said fluid pressure devices, andmeans including a slip connection for conducting fluid under pressure tosaid control valves from said source.

9. In a brick grinding apparatus, the combination set forth in claim 8and wherein each yoke arm includes a resilient friction strip engageablewith an adjacent face of the brick.

10. In a brick grinding apparatus for conditioning pairs of oppositefaces of bricks, in combination, a rotatable drum having peripherallyspaced cradles mounted thereon, means establishing a transfer station, acentering station, a grinding station and a discharge station incircumfer entially spaced relation about the drum in the order named,

rotatable grinding wheels at the grinding station and having opposedoperative surfaces for engaging adjacent opposite faces of brickspassing therebetween, a centering device. including a pair of centeringjaws at the centering station and movable between an'open position and aclosed position wherein the jaws engage the adjacent opposite faces ofthe bricks to align the bricks with the grinding wheels, a fluidpressure cylinder for actuating said centering jaws, a plurality ofcradles on the periphery of said drum and movable in successionrepeatedly past said station, each cradle including a fixed reaction jawand a movable clamping jaw movable between an open brick-releasingposition and a closed position wherein it engages a brick and forces thesame against the fixed reaction jaw, fluid pressure, means including afirst source of fluid under pressure for actuating each movableclarnping jaw to effect closing movement thereof during passage of theassociated cradle through the transfer station, to maintain the sameclosed during passage of the associated cradle through the centering andgrinding stations, and to open the same during passage of the associatedcradle through the centering and grinding stations, and to open the sameduring passage of the associated-cradle through the discharge station,and separate and second fluid pressure means including a second sourceof fluid under pressure for effecting momentary closing movement of thecentering jaws during passage of each cradle through the centeringstation and immediate opening thereof after such cradle has left thecentering station.

11. In a brick grinding apparatus, the combination set forth in claim 10and wherein said fluid pressure means for actuating'each movableclamping jaw comprises a pressure cylinder operatively connected to themovable jaw, a pressure accumulator, and a control valve having acontrol finger movable between first, second and third positions, saidcontrol finger when in its first position being effective to connect thefluid pressure device to the first source of'fluid under pressure so asto effect closing of the movable clamping jaw, said pressure accumulatorbeing connected to the pressure cylinder and biasing the latter toeffect closing of the movable clamping jaw, said control finger when inits second position being effective to seal off the pressure cylinderfrom said first source of fluid under pressure and permit the pressureaccumulator to become effective, said control finger when in its thirdposition being effective to connect the fluid pressure device to saidfirst source of fluid under pressure so as to effect opening of themovable clamping jaw, and a series of fixed cams positioned in the pathof movement of said control finger for moving the latter between thethree positions thereof.

12. In a brick grinding apparatus, the combination set forth in claim 10and wherein said second fluid pressure means for effecting momentaryclosing movement of the centering jaws comprises a pressure cylinderoperatively connected to said centering jaws, a fixed reversing valvefor the pressure cylinder and having a movable actuating finger movablebetween a first position wherein the valve is effective to open saidcentering jaws, and a second position wherein the valve is effective toclose said centering jaws, and a pair of finger-engaging cams on saiddrum successively engageable with said actuating finger for moving thesame between said first and second positions.

13. In a brick grinding apparatus, the combination set forth in claim 10and including, additionally, equalizing means for effecting equaldisplacement of said centering aws.

J 14. In a brick grinding apparatus, the combination set forth in claim10 and wherein said centering jaws are mounted for swinging movementstoward and away from each other, said centering jaws being provided withlateral extensions, and a pin and slot connection between said lateralextensions for equalizing the swinging movements of the jaws.

15. In a brick grinding apparatus, the combination with a grindingmachine adapted to receive a succession of similarly oriented bricks ata transfer station for conduction to a grinding station in orientedpositions which are dependent upon the orientation of the bricks whenreceived at the transfer station, of a feed conveyor for transportingthe bricks from a receiving station to the transfer station and forreleasing the bricks at the transfer station in such similarly orientedpositions, said feed con v veyor comprising an endless conveyor carrierhaving feed and return reach sections extending between the receivingstation and the transfer station, a series of articulatedbrick-supporting and transporting trays mounted on said carrier, eachtray including a crosshead, a pair of brickengaging jaws pivoted to thecrosshead and movable relatively toward and away from each other betweenclosed brick-engaging and open brick-releasing positions, spring meansyieldingly urging said jaws toward their open posi-. tion, meansoperatively connecting said jaws for equalize ing the movements thereof,a fixed latch arm on one of said jaws, and a pivoted latch arm on theother jaw and designed for latching engagement with the fixed latch armwhen saidjaws are moved to their closed position for maintaining thejaws in such closed position against the action of said spring means,cam means operable during movement of the trays along said return reachsection for effecting sequential closing of the jaws of said trays andconsequent latching engagement of the associated latch arms, and meansoperable upon arrival of each tray at, the transfer station andengageable with the associated 1 pivoted latch arm for moving the latterout of latching engagement with its respective fixed latch arm to effectopening of the associated jaws and consequent release of the bricksupported thereby.

16. In a brick grinding apparatus for conditioning pairs of end faces ofbricks, in combination, means establishing a receiving station, atransfer station, a grinding station and a discharge station, a feedconveyor adapted to receive bricks successively deposited thereon at thereceiving station, transport them in similarly oriented positions,

to the transfer station, and release them at said latter station, aclamping conveyor adapted to receive the released bricks at the transferstation, transport the same through the grinding station to thedischarge station and release them at said latter station, said feedconveyor comprising an endless carrier having feed and return reachsections extending between the feed and transfer stations and horizontalreversing sections at said feed and transfer stations, said clampingconveyor comprising a drum mounted for rotation about a horizontal axisbelow the reversing section of the feed conveyor at the transfer stationwhereby the region of closest approach between,

the two conveyors lies above the drum and constitutes the transferstation, a series of suspension arms pivotally mounted on the carrier atspaced points therealong and depending therefrom, an articulatedbrick-supporting tray carried at the lower end of each suspension armand movable between closed brick-supporting and open brickreleasingpositions, said suspension arms normally depending below the level ofthe transfer, station so that the cradles supported thereby are normallydisposed below such level, a fixed cam rail positioned in the path ofmovement of said suspension arms and engageable therewith for deflectingsaid arms as they approach the transfer station to raise the level ofthe trays to that of the transfer station and guide the trays throughthe transfer station, a

series of articulated brick-clamping cradles mounted on the periphery ofsaid drum for movement through said transfer, grinding and dischargestations, said cradles being movable between closed brick-clamping andopen brickdischarging positions, a pair of grinding wheels at said,

grinding station and having opposed operative surfaces, means fordriving said conveyors in timed relation so that the cradles and traysarrive at the transfer station in matched pairs, means effective toclose the trays during movement thereof from the-transfer station to thereceiving station, means effective to maintain said tiay's closed duringtheir movement from the receiving station to the transfer station, meanseffective to open the trays upon arrival thereof at the transferstation, means effective to open the cradles upon arrival thereof at thedischarge station and to maintain them open during their movement fromthe discharge station to the transfer station, and means effective toclose the cradles at the transfer station and maintain them closedduring passage thereof through the grinding station and to the dischargestation.

17. In a brick grinding machine, the combination set forth in claim 16,wherein said trays are yieldingly biased toward their open position,wherein the means for maintaining the trays closed comprises releasablelatch means, and wherein said means for opening said trays comprises aseries of trip fingers on the cradles engageable with the latch means onthe trays upon arrival of the cradles and trays at the transfer station.

18. In a brick grinding apparatus of the character described, a fixedgrinding stand including a pair of spaced apart grinding wheelspresenting opposed parallel grinding surfaces for simultaneouslygrinding the adjacent opposite faces of successive bricks moving betweensaid surfaces, a rotatable brick-supporting drum for conducting thebricks endwise and successively between said grinding surfaces, and aplurality of brick-supporting and clamping cradles carried on theperiphery of said drum and movable past a loading station where thebricks may be applied to the cradles and past a discharge station wherethe bricks are discharged from the cradles, each cradle comprising apair of side plates secured to opposite sides of the drum and presentingstraight outer edges which extend generally tangentially of the drum andacross which edges a brick received Within the cradle is adapted toextend with the end regions of the brick overhanging the same onopposite sides of the drum, the leading ends of said plates beingprovided with generally radially outwardly projecting extensionsconstituting a fixed clamping jaw, a yoke pivoted to the outer end ofeach clamping jaw, a pair of resilient clamping members mounted on eachyoke and designed for clamping engagement with adjacent brick faces,said clamping elements, when in contact with said adjacent brick faces,allowing for lateral shifting for the bricks in the cradles under theinfluence of grinding pressure on the brick faces being ground, a pairof levers pivoted medially of their ends to said side plates adjacent totheir trailing ends and presenting jaw arms outside the cylindricalconfines of the drum and jaw-actuating extensions within the cylindricaldrum confines, said jaw arms constituting a movable jaw capable ofswinging movement toward and away from said fixed jaw between retractedopen and advanced closed positions, the inner ends of said extensionsbeing slotted, a pair of crank arms, one pair for each cradle, mountedon the drum and having pins operating in the slots of said extensions,actuating cylinders mounted on the drum and operatively connected to thepairs of crank arms, control valves mounted on the drum for actuatingthe cylinders, means for supplying fluid under pressure to said controlvalves, an actuating finger on each control valve, and fixed camspositioned in the path of movement of said actuating fingers andengageable therewith in passing for sequentially actuating the controlvalves to effect closing movements of said movable jaws at the loadingstation and opening thereof at the discharge station.

19. In a brick grinding apparatus of the character described, thecombination set forth in claim 18 and including, additionally, a yokepivoted to the outer end of each clamping jaw, and a pair ofanti-friction members mounted on each yoke and designed for clampingengagement with adjacent brick faces, said anti-friction members, whenin contact with said brick faces, allowing for lateral shifting of thebricks in the cradles under the influence of grinding pressure on thebrick faces being ground.

20. In a brick grinding apparatus, a support, a bricksupporting andclamping drum mounted on said support for' rotation about an axis, amotor drivingly connected t6 the drum for rotating the latter, aplurality of brickclamping cradles mounted on the periphery of said drumand movable through a loading station, a centering station, a grindingstation and a discharge station successively and in the order named, apair of brick-clamping jaw-s associated with each cradle and movablebetween closed brick-clamping and open brick-releasing position, apressure cylinder operatively connected to each pair of jaws foractuating the same, a control valve for each cylinder, a pressureaccumulator for each cylinder, said pressure accumulator being effectiveto actuate the cylinder so as to maintain said clamping jaws closed,said control valve being effective in a first position to actuate thecylinder so as to effect jaw-closing movements, in a second position toclose off said cylinder and allow said pressure accumulator to becomeeffective, and in a third position to actuate the cylinder to effectjaw-opening movements, all of said cylinders, pressure accumulators andcontrol valves being operatively mounted on the drum for rotation bodilytherewith, each control valve having a movable control lever associatedtherewith for selectively effecting the position of the valve, first,second and third fixed cams positioned on said support in the path ofmovement of said control levers and designed for successive engagementtherewith upon rotation of the drum, said first cam being effective tomove the valves to their first position when the corresponding cradlesmove through the loading station, said second cam being effective tomove the valves to their second position when the corresponding cradlesmove through the centering station, and the third cam being effective tomove the valves to their third position when the corresponding cradlesmove through the discharge station.

21. In a brick grinding apparatus, a support, a bricksupporting andclamping drum mounted on said support for rotation about a horizontalaxis, a motor drivingly connected to the drum for rotating the latter, aplurality of brick-clamping cradles mounted on the periphery of the drumand movable through a loading station, a centering station, a grindingstation and a discharge station in the order named, a pair ofbrick-clamping jaws associated with each cradle and movable betweenclosed brick-clamping and open brick-releasing positions, fluid pressuremeans effective to cause closing movements of the jaws as the associatedcradles move through the loading station and to cause opening movementsof the jaws as the associated cradles move through the dischargestation, a pair of centering shoes on opposite sides of the drum at thecentering station and movable toward and away from each other in unisonbetween retracted inoperative and advanced operative positions andeffective, when in their operative position to engage the side faces ofa brick passing through the centering station to align the same with thegrinding station, a fluid pressure cylinder for actuating said centeringshoes, a source of fluid pressure, a control valve operatively connectedto the source of fluid pressure and the pressure cylinder for actuatingthe latter, said control valve being effective in a first position toretract said centering shoes and in a second position to advance saidcentering shoes, a valve actuator for controlling the positions of saidvalve, and a series of control cams mounted on the drum, movable bodilytherewith and engageable with said valve actuator in succession andeffective to cause advance movement of the centering shoes duringmovement of each cradle through the centering station.

22. In a brick grinding apparatus, the combination set forth in claim21, wherein said valve actuator is yieldingly biased to a positionwherein said centering shoes are in their inoperative retractedposition, and wherein said control cams on the drum are in the form oftrip fingers for momentarily engaging the actuator in passing.

23. In a brick grinding apparatus, a support, a bricksupporting andclamping drum mounted on said support for rotation about a horizontalaxis, a motor drivingly connected to the drum for rotating the latter, aplurality of brick-clamping cradles mounted on the periphery of the drumand movable through a loading station, a centering station, a grindingstation and a discharge station in the order named, a pair ofbrick-clamping jaws associated with each cradle and movable betweenclosed brickclamping and open brick-releasing positions, fluid pressuremeans effective to cause closing movements of the jaws as the associatedcradles move through the loading station and to cause opening movementsof the jaws as the associated cradles move through the dischargestation, a centering device at said centering stationand comprising asupport, a pair of rocker arms pivoted to said support at spaced pointsthereon, adjacent ends of said rocker arms carrying opposed centeringshoes on opposite sides of the drum, said shoes being movable with thearms toward and away from each other between advanced operativepositions wherein the shoes engage the side faces of a brick 20 passingthrough the centering station to align the same with the grindingstation, and retracted inoperative positions, a pressure cylinderinterposed between said rocker arms for actuating the same, a source offluid pressure, a

control valve operatively connected to the source of, fluid tering shoesare retracted and in a second position to move the rocker arms topositions wherein said centering shoes are advanced, a valve actuatorfor controlling the positions of said valve, and a series of controlcams mounted on the drum, movable bodily with the drum, and engageablewith said valve actuator in succession to cause advance movement of thecentering shoes during movement of the cradles through the centeringstation.

References Cited by the Examiner UNITED STATES PATENTS 406,450 7/1889Casse 51-2152 766,403 8/1904 Vincke 51l18 1 1,166,647 1/1916 Wolfe198-210 1,646,359 10/1927 Raiche 198103 2,000,458 5/1935 Shipley 51--1342,352,551 6/1944 Kende 51-118 2,799,124 7/1957 Polzin 51215.1

HAROLD D. WHITEHEAD, Primary Examiner.

1. IN A BRICK GRINDING APPARATUS FOR CONDITIONING PAIRS OF OPPOSITEFACES OF BRICKS, IN COMBINATION, MEANS ESTABLISHING A RECEIVING STATION,A TRANSFER STATION, A GRINDING STATION AND A DISCHARGE STATION, A FEEDCONVEYOR HAVING A FIXED FRAMEWORK AND INCLUDING A SERIES OFBRICK-SUPPORTING TRAYS MOVABLE IN FEED AND RETURN RELATION BETWEEN THERECEIVING AND TRANSFER STATIONS AND ADAPTED TO RECEIVE A SUCCESSION OFBRICKS AT THE FORMER STATION AND TRANSFER THEM TO THE LATTER STATION, ABRICK-CLAMPING CONVEYOR HAVING A FIXED FRAMEWORK AND INCLUDING A SERIESOF BRICKCLAMPING CRADLES MOVABLE IN ADVANCE AND RETURN RELATION BETWEENTHE TRANSFER AND GRINDING STATIONS AND ADAPTED TO RECEIVE THE BRICKSFROM THE FEED CONVEYOR AT THE TRANSFER STATION AND CONDUCT THEM TO THEGRINDING STATION, A PAIR OF GRINDING WHEELS AT THE GRINDING STATION ANDHAVING OPPOSED GRINDING SURFACES BETWEEN WHICH THE CLAMPED BRICKS IN THECRADLES ARE ADAPTED TO PASS, EACH TRAY INCLUDING A PAIR OF TRAY SECTIONSMOVABLE BETWEEN CLOSED BRICK-SUPPORTING AND OPEN BRICK-RELEASINGPOSITION, SPRING MEANS YIELDINGLY URGING SAID TRAY SECTIONS TOWARD THEIROPEN POSITION, LATCH MEANS AUTOMATICALLY OPERABLE TO MAINTAIN THE TRAYSECTIONS IN THEIR CLOSED POSITION AGAINST THE ACTION OF SAID SPRINGMEANS, CAM MEANS OPERABLE DURING THE RETURN MOVEMENTS OF THE TRAYS FORMOVING SAID TRAY SECTIONS TO THEIR CLOSED POSITION, EACH CRADLEINCLUDING A PAIR OF BRICKCLAMPING JAWS MOVABLE BETWEEN CLOSEDBRICK-CLAMPING AND OPEN BRICK-RELEASING POSITIONS, MEANS FOR MOVING SAIDCONVEYORS IN TIMED RELATION SO THAT THE TRAYS AND CRADLES ARRIVE INMATCHED PAIRS AT THE TRANSFER STATION, MEANS OPERABLE UPON ARRIVAL OFEACH TRAY AT THE TRANSFER STATION TO TRIP THE LATCH MEANS THEREOF TOOPEN THE TRAY SECTIONS AND RELEASE THE BRICK SUPPORTED THEREBY, MEANSOPERABLE UPON ARRIVAL OF EACH CRADLE AT THE TRANSFER STATION TO CLOSETHE JAWS THEREOF IN ORDER TO CLAMP THEREBETWEEN A BRICK RELEASED FROMTHE FEED CONVEYOR, AND MEANS OPERABLE UPON ARRIVAL OF EACH CRADLE AT THEDISCHARGE STATION FOR OPENING THE JAWS THEREOF TO RELEASE THE GROUNDBRICKS.